Car-door interlock



Aug. 6, 1929. l J. C MCCUNE 1,723,192

GAR DOOR INTERLOCK Filed May 19. 1928 INVENTOR ATTORNEY Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

`JOSEPH C. MCCUNE, 0F EDGEWOOD, CPENNSYLVANIA, ASSIGNOR yTO THE WESTING- HOUSE AIR BRAKE COMPANY, OF WILTERDING, PENNSYLVANIA, A CORPORATION CAR-DOOR INTERLOCK.

Appiicauon filed May i9,

pressure is supplied to apply'the brakes and y is also supplied to a door engine to effect the opening or thecar doors.

`Witli the above etpiipinent, the brake cylinder pressure will build up to the lull pressure carried in the main reservoir it the brake 'valve .is left in the door open position, and in order `to avoid this and prevent the unnecessary waste oli iluid under pressure, it has also been proposed to provide ineans lor limiting 'the pressure of fluid supplied to the brake cylinder in the door yopen position oli the brake valve. The brake valve device ot' tliisequipnient is also provided with another position :tor applying the brakes without opening the car doors and 'in which the presf sure in the brake cylinder iiiay 'be built up as desired to the limit ot kpressure carried in the main reservoir. y u

In order to avoid a rough stop, it is necessary that the operator applythe brakes and then graduate the pressure down asy the train approaches a stop and then in order-to open the car doors, it is necessary-to inove the brake valve handle to the door open posit-ion atter the car has actually been brought to a stop and in this .position fluidA under pressure .is again supplied to the brake cylinder up to the pressure of the ressure limiting devicey` y rllhe principal object et my invention is to provide an apparatus for controlling the car doorsI and the brakes .in which tluidunder pressure is `not supplied to the brake cylinder in operating' the apparatus to open the car doors until the car doorsk have been opened. i

1n the accompanying drawing g Fig. l is a diagrammatic view, mainly iir section, of a cai.' door and brake controlling' equipment embodying ni'y invention; Fig. 2 a sectional view ot the brake valve device,-showing the rotary valve in service brake application,

doors closed position; Fig. 3 a sectional view oit the brake valve device, showing the rotary valve in the door opening position; and

n 1S) at one side'ol piston 1923. Serial No. 278,995.

Fig. 4 a sectional view of ythe door engine, shown in the door open position.

The equipment shown in the drawing coinprises a brake valve device 1, adoor engine 2, a brake cylinder 3, a main reservoir 4, a magnet valve device 5, and a pressure liniiting valve device 6. l

The brake valve device l may comprise a casing having a valve chamber `7 connected by pipe S to the main reservoir .land containa rotary valve 9 adapted to be operated by a. handle 10. The door engine 2y may coii'ipi'ise a casing having a piston cylinder containing pistons 11 and l2. The pistons 1l. and 12 rare connected together by a rack bar 13, a gear segment lilY being provided with teeth` adapted to mesh with the teeth of 'tlierack bar. K

The gear segment 14' is adapted to operate a. shalft 15, the rocking of which is adapted to operate n'ieclianism for effecting the opening and closing of a car door. A pipe 16 leads Afrom piston chamber 17 at one side of pistonll to the seat of the rotary valve 9 and a pipe 18 leads from piston chamber 12 to the seat of said rotary valve. i

According to my invention7 a contact ineniber 2O yis carried by the gear segment 14; and in the door opening position of the segiiient, the member 20 is adapted to bridge contact lingers`21 and 22.r The linger 21 is connected to a source of current wire 23 and the contact finger 22 is connected to a wire 24 which leads to one terminal of a magnet 25 of the magnet valve device 5.

The magnet 25 is adapted to operate a valve 26 .tor controlling communication from a fluid pressure supply pipe 27, connected to the` main reservoir 4l, to the brake cylinder 3. The pressurelimiting valve device 6 isinterposed/in the pipe 27 and comprises a ball check valve 28 which is urgedto its seat by a spring 29.

For the sake of simplicity, certain units of the usual brake-and door controlling equipiiient are not shown in the drawing, since the invention will be clearly understood without showing the complete working equipment. For example, the emergency brake pipe 30 connected to an emergency valve device (not shown) which is adapted to operateupon a reduction inv fluid pressure in the emergency brake pipe to supply fluid under pressure to the brake cylinder 3.

In the release position of the brake valve device, as shown `in Fig. 1, the brake pipe 30 is connected through port 31 in the rotary valve with the valve chamber 7 and is also connected through cavity 32 in the valve, with the pipe 18, so that fluid under pressure is supplied to piston ehamberpl) ot the door engine 2. Pipe 16 is connected through cavity 33 .in the rotary valve With an atmospheric exhaust port 3d, so that piston chamber 17 is at atmospheric pressure, and the pistons 11 and 12 are held in the position shown in Fig. 1, in which the gear segment 14 is positioned to hold the car door closed. In this position, the contact member 20 is out of engagement with the contact lingers 2l and 22, so that the magnet 25 remains deenergized. I V

In'the release position, the straight air pipe 35 is connected through cavity 33 in the rotary valve 9 With exhaust port 34, so rthat the brake cylinder 3 is at atmospheric pressure.

If the operator Wishes to effect a service application of the brakes, Without opening the car doors, he moves the brake valve handle 10 to service position, doors closed, as shown in Fig. 2. In this position, the emergency brake pipe 30 remains connected to the door closing pipe 18, through cavity 36 in the rotary valve, and the door opening pipe 16 is connected to .the exhaust port 3a through cavity 37.

The straight air pipe35 is connected to the rotary valve chamber 7, through port 38, so that fluid under pressure is supplied to the brake cylinder 3 to effect a service application of the brakes. It it is desired to open the car doors, the brake valve is turned to the position shown in Fig. 3. In this position, the door closing pipe 18 is y connected, through cavity 39 With exhaust port 34, While the door opening pipe 16 is connected, through port l0 with the rotary valve chamber 7.

Fluid under pressure being then supplied through pipe 16 to piston chamber 17, the pistons 11 and 12 are shifted to the right to the position shown in Fig. 4l, so as to eliiect the opening of thecar doors.

It will be noted that in the door opening position of the brake valve device, the

Vstraight air pipe-35 is lapped, so that in this position, fluid under pressure is not supplied to the brake cylinder. Then the door engine moves to Vthe door opening position, the movement of the gear segment llcauses the Contact member 2O to bridge the contact lingers 21 and 22.

Current is then supplied to energize the magnet 25, so that the valve 26 is unseated and fluid under pressure is permitted to floW from the pipe 27 to the brake cylinder 3.

Vthe valve.

lllhile one illustrative embodiment of the invention has been described in detail, it is not my intent-ion to limit its scope to that embodiment or otherwise than by the terms of the appended claims.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The combination With a brake cylinder, of a door engine and means operated upon movement of the door engine to the position for opening the car doors for supplying fluid under pressure to the brake cylinder.

2. The combination With a brake cylinder, of a device for eifecting the opening and closing of a car door and means operated by the movement oi said device to the door opening position for supplying fluid under pressure to the brake cylinder.

The combination with a brake cylinder, of electrically controlled means for controlling the supply of `Fluid under pressure to the brake cylinder, a mechanism operative to eiiect the opening and closing of a car door, and means operated by said mechanism for controlling said electrically controlled means.

fl. The combination With a brake cylinder, of electrically controlled means operated upon energization to eli'ect the supply of fluid under pressure to the brake cylinder, a

door engine for effecting the opening and closing of a car door, and means operated upon movement of said door engine to the door opening position, for effecting the energization of said electrically controlled means.

5. rlhe combination with a brake cylinder, of mechanism for effecting the opening and closingA of a car door, means operated upon movement of said mechanism to effect the opening of 4a car door for supplying fluid under pressure to the brake cylinder, and means for limiting the pressure of fluid supplied to the brake cylinder by the first mentioned means.

6. The combination with a brake cylinder, of a door engine, a brake valve device for controlling the operation of said door engine and the supply of fluid under pressure to the brake cylinder and having one position in Which the door engine is maintained in the door closing` position and in which fluid under pressure is supplied to the brake cylinder, and another position in which the door engine is operated to elfect the opening of a.

rar door and in ivhich lluidunder pressure is not rsupplied to the brake cylinder, and means operated upon movement of said door engine tothe door opening position for supciosing of a cau door, and a switch device piying fluid under pressure to the brake operated upon movement of said mechanism 10 cylinder. f to the position for opening a car door for 7. The combination with :L brake cylinder, closing a circuit to effect the energization of 5 of :i magnet valve device operated upon seid magnet valve device. y

enei'gization for eiiiecting the supply of In testimony whereof I have hereunto set fluid under presente to the brake cylinder, a my hand, this 16th day .of May, 1928. mechanism foi effecting Vthe opening and JOSEPH C. MCCUNE. 

